Liquid crystal polymer (LCP) films with properties such as high thermal resistance, low dielectric constant, low dielectric loss, high dimensional stability, low moisture adsorption, flame retardancy, and recyclability may replace the thermosetting polyimide film in the application of flexible boards of next generation. The conventional FCP films have an overly high thermal expansion coefficient, which cannot match a copper foil to form a copper clad laminate. Accordingly, a LCP film with low thermal expansion coefficient for being applied in a copper clad laminate is called-for.